Cloud serves, which emerged accompanying the development of the virtualization technology, are now used over a very wide variety of fields. Meanwhile, virtualization infrastructure systems for providing cloud services are becoming larger and more complicated in recent years, making it difficult to respond to problems such as system abnormalities and disorders.
FIG. 1 illustrates an example of a cloud infrastructure system and an analysis device. A cloud infrastructure system 1000 includes a plurality of shared switches 1100 and a plurality of shared servers 1200. The plurality of shared servers 1200 can communicate to each other via the shared switches 1100. The plurality of shared servers 1200 share computer resources so as to implement one cloud infrastructure system.
Specifically, the plurality of shared servers 1200 cooperate so as to operate a host Operation System (OS) 2001. The host OS 2001 is software, for managing the entire system, that implements a function for fundamental management and control of the plurality of shared servers and a fundamental function that is used by the pieces of installed software. Note that the plurality of shared servers 1200 may operate the plurality of host OSs 2001.
On the host OS 2001, a hypervisor 2002 operates. The hypervisor 2002 is a control program for implementing a virtual machine (VM), which is a virtualization technique for computers. On the hypervisor 2002, a plurality of virtual machines 2003 (virtual machines 2003a through 2003c for example) operate.
As a service according to a cloud infrastructure system, each of the virtual machines 2003a through 2003c is provided to the user. The user can operate one of the virtual machines 2004a through 2004c on the virtual machines 2003 that he or she can use.
In the cloud infrastructure system 1000 as described above, the user can obtain application performance information of the virtual machines 2003 that he or she can use. Application performance information is time-series data that represents the performance of an application operating on the cloud. Application performance information is time-series data such as for example a response time and throughput for a web access, a response time and throughput for a database query, a process time and throughput for a data process, etc.
The system performance information of the cloud infrastructure system 1000 is transmitted to an analysis device 3000. System performance information is time-series data representing the system performance and the load condition that can be obtained from the cloud infrastructure system. Examples of the system performance information include the CPU (Central Processing unit) use rate and the virtual CPU use rate of the server, network throughput, virtual Network Interface Card (NIC) throughput, etc. The administrator uses the performance information collected in the analysis device 3000 so as to manage the performance of the cloud infrastructure system 1000. Note that the user can obtain part of the system performance information of the virtual machines 2003 that he or she can use.
When a problem occurs in the system, the administrator analyzes log information, statistical information, configuration information, system performance information, etc. collected in the analysis device 3000 so as to presume the cause of the problem and make a recovery promptly. In a cloud infrastructure system, it is difficult to perform manual analysis for all information including log information, statistical information, configuration information, system performance information, etc. Causes of problems of virtualization systems particularly may be generated on a wide range of layers (layers of the applications 2004, the virtual machines 2003, the hypervisor 2002, the host OS 2001, the shared servers 1200, the shared switches 1100, etc.). At the same time, a different administrator often manages each layer, which makes it difficult to respond to problems.
In the cloud infrastructure system 1000 illustrated in FIG. 1, the layer of the applications 2004 is managed by the user. Meanwhile, the layers of the virtual machines 2003, the hypervisor 2002, the host OS 2001, the shared servers 1200, the shared switches 1100, etc. are managed by the administrator.
When performance deterioration such as a slowdown in the processing speed of the application has occurred in the application 2004 used by a user, the administrator receives a report of the performance deterioration from the user. In the cloud infrastructure system, the computer resources of the shared servers 1200 are used by a different virtual machine in competition with the application. Accordingly, the administrator analyzes for example log information, statistical information, configuration information, system performance information, etc. collected in the analysis device 3000 so as to presume a virtual machine that is a cause of the performance deterioration.
In order to presume a virtual machine, the administrator first receives the application performance information of the application from the user. The administrator estimates the performance information of a virtual machine having a correlation with the application performance information by using the analysis device 3000. This makes it possible to presume a virtual machine that is a cause of the performance deterioration of the application used by the user.
When the correlative relationship between the performance information of a virtual machine and the application performance information is effective only during a temporary period of time, the analysis device 3000 fails to presume a virtual machine causing the performance deterioration in some cases. Thus, when the correlative relationship between the performance information of a virtual machine and the application performance information is effective only during a temporary period of time, the presumption performance, which represents the degree to which a virtual machine causing performance deterioration can be presumed, deteriorates.
A system that detects performance deterioration in a system for providing information communication services is known. The system generates a correlation function representing a correlation coefficient between different types of performance information, provides the obtained performance information to the correlation function so as to analysis whether or not the correlative relationship is maintained, and thereby detects performance deterioration (see Patent Document 1 for example).
A technique of using a correlation rule for extracting a column in a correspondence relationship between two pieces of data is known (see Patent Document 2 for example).
An analysis system that simply and securely identifies an explanatory variable influencing an objective variable is known regarding an objective variable related to the quality of settled objects and an explanatory variable related to the production of settled objects.
A device that uses resource information of a virtual machine is known. A virtual machine arrangement device determines the predictability of a resource use amount, and simultaneously levels the time-series pattern of the predicted resource use amount and any types of resource use amounts for a predictable virtual machine (see Patent Document 4, for example).
A method is known in which a fundamental image represented by multiple-valued data is binarized by applying a circulation error diffusion method so as to reduce generated noise by utilizing the binarization of the fundamental image.
Patent document 1: Japanese Laid-open Patent Publication No. 2014-238852
Patent document 2: Japanese Laid-open Patent Publication No. 2012-38066
Patent document 3: Japanese Laid-open Patent Publication No. 2006-318263
Patent document 4: Japanese Laid-open Patent Publication No. 2015-152984
Patent document 5: Japanese Laid-open Patent Publication No. 10-233923